"I'm a little bit pessimistic again," he said. "I don't feel like we're as good as we need to be right now, but I feel like we're in a better position than we were last year."

Whether Stewart is a factor will be determined as the Chase for the Sprint Cup plays out in coming weeks. For now, the Columbus, Ind. native is among a wide-open field as the Joliet oval hosts the Geico 400 Chase kickoff race for the second straight year.

Stewart barely made the final 12-driver field in 2011, used a victory at Chicagoland as a springboard to four more series wins an eventual Sprint Cup triumph.

"Last year I obviously proved I'm that I'm not very good at predicting things and picking," the 41-year-old veteran said at a Wednesday preview featuring all 12 finalists. "I don't think Vegas is going to call me and ask me to handicap anything."

Stewart held off Carl Edwards in the final Chase race at Homestead-Miami Speedway to win the 2011 finale, tie for first in the final standings and take the title on a tiebreaker.

"It was spectacular to knock down five wins ... he won half the races in the Chase," Johnson said on Wednesday. "And he had to to tie Carl."

NASCAR president Mike Helton said that memorable finish would be hard to top.

"We basically had two champions last year," Helton said at a Wednesday fan event. "As it got down to (Tony) and Carl is was a matter of having to do everything perfectly in order to come out as a champion.

Stewart is no stranger to success. He also won NASCAR championships in 2002 and 2005 and was 1997 Indy Racing League champ. He's also performed well at Chicagoland Speedway with one pole position, three victories, eight top fives and nine top 10s.

After the 2011 triumph, Stewart parted ways with crew chief Darian Grubb and brought on Steve Addington, who switched from Kurt Busch's crew. Grubb eventually signed on with Denny Hamlin, who emerged as points leader entering the Chase.

"I don't think we gave up on Darian as much as we just needed a change," Stewart said. "You've got to do what you think as an owner to try to give yourself the best opportunity to have success. You don't look back, you don't say say 'what if'."

Stewart, who drives for and co-owns Stewart-Haas Racing, claimed 10 top five finishes this year including two wins in the season's first five races (Las Vegas and at Fontana, Calif.) and another at Daytona on July 7.

Three weeks later, the season was also marred by a spat with driver Matt Kenseth. In an Aug. 1 incident as their cars bumped at Bristol Motor Speedway. Later in pit row, Stewart threw his helmet at the hood of Kenseth's car and promised to run over his rival in future races.

Cooler heads eventually prevailed and the controversy blew over.

Stewart closed the regular season with a fourth-place finish at last Saturday's rain-soaked and delayed Richmond race and entered the Chicagoland race ranked third overall.

Coming into the Chase, Stewart said it's dangerous to look beyond the task at hand.

"It's literally a one-week at a time scenario," he said. "One point can make a difference whether it's leading a lap or even a day where you may get into a crash and you're running 30th and you can get to 29th, that one point can make a difference."